EP3032383A1

EP3032383A1 - Light-transmitting conductive member and patterning method thereof

Info

Publication number: EP3032383A1
Application number: EP14834028.4A
Authority: EP
Inventors: Tomoyuki Yamai; Mitsuo Bito; Yasuyuki Kitamura
Original assignee: Alps Electric Co Ltd
Current assignee: Alps Alpine Co Ltd
Priority date: 2013-08-05
Filing date: 2014-07-15
Publication date: 2016-06-15
Anticipated expiration: 2034-07-15
Also published as: JPWO2015019805A1; CN105474140A; EP3032383B1; US20160139710A1; EP3032383A4; CN105474140B; US9965124B2; WO2015019805A1; JP6058141B2

Abstract

To provide a light transmitting electrically conductive member in which an electrically conductive layer containing silver nanowires can be patterned into an electrically conductive region and a non-electrically conductive region and in which optical characteristics of the non-electrically conductive region can be improved, and also to provide a method for patterning the light transmitting electrically conductive member.
[Solution] A light transmitting laminate material in which an electrically conductive layer 12 including an overcoat layer 14 and silver nanowires 13a embedded therein is formed on a surface of a light transmitting base film 11 is used, and a step of treating a surface of the electrically conductive layer 12 which is not covered with a resist layer 41 using an iodine solution to at least partially iodize the silver nanowires 13a and a step of applying a thiosulfate solution to the surface of the electrically conductive layer 12 which is not covered with the resist layer 41 to remove a silver iodide exposed to a surface of the overcoat layer 14 are performed. Since a white cloudy or a whitened silver iodide is removed, the optical transmission characteristics of the non-electrically conductive region can be improved.

Description

Technical Field

The present invention relates to a light transmitting electrically conductive member in which an electrically conductive region is partitioned from a non-electrically conductive region and a method for patterning the same.

Background Art

A light transmitting electrically conductive member disposed at a front side of a display panel has been used as an electrostatic touch panel or the like.
In a related light transmitting electrically conductive member, although a light transmitting electrode layer formed on a surface of a base material is formed from indium tin oxide (ITO), this type of metal oxide is disadvantageously weak against a bending stress. In Patent Literature 1, a light transmitting electrically conductive layer which includes a resin layer and a network of electrically conductive nanowires embedded therein has been disclosed. Since being strong against an external physical force, such as a bending stress, the electrically conductive layer described above is suitably used for a light transmitting electrically conductive member which includes a bending deformable resin film as a base material.
In the electrically conductive layer containing electrically conductive nanowires, a patterning may be performed by an etching step so that a non-electrically conductive region is partially formed by dissolving the electrically conductive nanowires. However, after the patterning is performed, there has been a problem in that between an electrically conductive region in which the electrically conductive nanowires remain and the non-electrically conductive region from which the electrically conductive nanowires are removed, a remarkable difference in optical characteristics is generated.
Accordingly, Patent Literature 1 has also disclosed a step in which the electrically conductive nanowires are partially chemically transformed into non-electrically conductive nanowires or nanowires having a high resistivity. In the step described above, by applying an oxidizing agent to a region which is required to be non-electrically conductive, silver nanowires are changed into an insoluble metal salt by modification so as to have non-electrically conductive properties.

Citation List

Patent Literature

PTL 1: Japanese Unexamined Patent Application Publication No. 2010-507199

Summary of Invention

Technical Problem

In an electrically conductive layer including a network of electrically conductive nanowires, in order to ensure the electrical conductivity with a metal layer or the like to be formed on the electrically conductive layer, the nanowires are partially exposed to the surface thereof. Hence, when an oxidizing agent is applied to a region which is required to be non-electrically conductive, the nanowires exposed to the surface of the electrically conductive layer are formed into a metal oxide compound and remain in the form of a white cloudy material, and as a result, a problem in that the optical characteristics of the region which is required to be non-electrically conductive are degraded may arise.
In addition, in Patent Literature 1, as the oxidizing agent, an oxide salt, such as a hypochlorite, or an organic oxidizing agent, such as tetracyanoquinodimethane (TCNQ), has been disclosed by way of example. However, those oxidizing agents each have not an adequate degree of permeation into an overcoat layer, which is a resin layer, in which a network of silver nanowires is embedded, and hence, patterning to partition the electrically conductive region from the non-electrically conductive region is difficult to be precisely controlled. In addition, when a lead layer is formed on the electrically conductive layer containing silver nanowires using a metal layer of copper or silver, a problem may arise in that this metal layer is liable to be damaged.
The present invention solves the related problems described above and aims to provide a light transmitting electrically conductive member capable of reducing the difference in optical characteristics between an electrically conductive region and a non-electrically conductive region when an electrically conductive layer is partially modified to the non-electrically conductive region.
In addition, the present invention also aims to provide a method for patterning a light transmitting electrically conductive member, the method being capable of precisely performing a treatment in which an electrically conductive region is partitioned from a non-electrically conductive region by partially modifying an electrically conductive layer. Solution to Problem
In a light transmitting electrically conductive member of the present invention in which an electrically conductive layer including an overcoat layer and silver nanowires embedded therein is formed on a surface of a light transmitting base material,
the electrically conductive layer is partitioned into an electrically conductive region and a non-electrically conductive region having a high surface resistivity as compared to that of the electrically conductive region, and in the non-electrically conductive region, the silver nanowires embedded in the overcoat layer are at least partially iodized, and
a silver iodide is not exposed to a surface of the overcoat layer in the non-electrically conductive region, or the amount of a silver iodide exposed to the surface of the overcoat layer in the non-electrically conductive region is small as compared to the amount of silver nanowires exposed to a surface of the overcoat layer in the electrically conductive region.
In the light transmitting electrically conductive member of the present invention, when the silver nanowires in the non-electrically conductive region are transformed into a silver iodide, the surface resistivity can be increased as compared to that of the electrically conductive region without significantly changing the light transmittance from that of the electrically conductive region. In the non-electrically conductive region, the silver iodide is not present on the surface of the overcoat layer, or even if the silver iodide is present thereon, the amount of the silver iodide is very small; hence, a white cloudy silver iodide is hardly present on a surface of a non-electrically conductive layer, the haze in the non-electrically conductive region is reduced, and as a result, the transparency thereof can be maintained high.
In addition, in this specification, the amount of the nanowires exposed to the surface of the overcoat layer indicates the total mass of the nanowires exposed to the surface per unit area. Alternatively, the amount of the nanowires exposed to the surface of the overcoat layer indicates the area rate of the nanowires exposed to the surface per unit area.
Next, a method for patterning a light transmitting electrically conductive member of the present invention uses a light transmitting laminate material in which an electrically conductive layer including an overcoat layer and silver nanowires embedded therein is formed on a surface of a light transmitting base material and comprises the steps of:

covering a part of the electrically conductive layer with a resist layer;
treating a surface of the electrically conductive layer which is not covered with the resist layer using an iodine solution to at least partially iodize the silver nanowires; and
applying a thiosulfate solution to the surface of the electrically conductive layer which is not covered with the resist layer to remove a silver iodide exposed to a surface of the overcoat layer.

The iodine solution is an iodine-potassium iodine solution, and the concentration of iodine and the concentration of potassium iodine in the solution are preferably 0.05 to 1.0 percent by mass and 0.1 to 5.0 percent by mass, respectively.
In addition, the thiosulfate solution is a sodium thiosulfate solution, and the concentration of sodium thiosulfate is preferably 1.0 to 25 percent by mass.
In the method for patterning a light transmitting electrically conductive member of the present invention, since the step of removing a silver iodide is provided after the treatment step of iodizing silver nanowires, iodized silver nanowires exposed to the surface of the overcoat layer can be removed, so that the haze of an insulating layer can be reduced, and the transparency thereof can be improved.
Since the iodine-potassium iodine solution is likely to permeate the overcoat layer and can easily transform the silver nanowires in the electrically conductive layer in the region which is not covered with the resist layer into a silver iodide, the boundary between the electrically conductive region and the non-electrically conductive region can be precisely patterned.
The thiosulfate solution is not likely to permeate an acrylic-based overcoat layer or the like, and hence, the iodized silver nanowires present in the overcoat layer in the non-electrically conductive region are not so much influenced. Hence, even after the treatment for removing a silver iodide exposed to the surface of the overcoat layer is performed by applying a thiosulfate solution, the silver nanowires having an increased surface resistivity are allowed to remain in the overcoat layer, and the difference in optical characteristics between the non-electrically conductive region and the electrically conductive region can be reduced. In addition, since the thiosulfate solution is not likely to permeate the overcoat layer, the amount of a thiosulfate solution which remains in the overcoat layer is small, and furthermore, since the thiosulfate solution has a low oxidizing power, copper, silver, and/or the like to be used to form the lead layer on the surface of the electrically conductive region is not likely to be damaged.

Advantageous Effects of Invention

In the light transmitting electrically conductive member of the present invention, since the silver nanowires in a specific region is transformed into a non-electrically conductive silver iodide or a silver iodide having a high resistance, the electrically conductive region can be partitioned from the non-electrically conductive region without completely removing the silver nanowires. In addition, in the non-electrically conductive region, since a silver iodide is hardly exposed on the surface of the overcoat layer, a white cloudy metal compound or a whitened metal compound is suppressed from remaining on the surface of the non-electrically conductive region, and as a result, the optical transmission characteristics can be improved. In addition, since the silver nanowires are allowed to remain in the overcoat layer in the non-electrically conductive region, the difference in optical characteristics between the non-electrically conductive region and the electrically conductive region can be reduced.
In the method for patterning a light transmitting electrically conductive member of the present invention, since silver nanowires are processed to be substantially non-electrically conductive using an iodine solution which is likely to permeate the overcoat layer, patterning to partition between the electrically conductive region and the non-electrically conductive region can be easily controlled. In addition, although a silver iodide exposed to the surface of the overcoat layer is removed by a thiosulfate solution, since the thiosulfate solution is not likely to permeate the overcoat layer, the amount of a thiosulfate solution remaining in the overcoat layer is small, and furthermore, since the thiosulfate solution has a low oxidizing power, a metal layer to be formed on the overcoat layer can be easily prevented from being damaged.
In the patterning method of the present invention, the iodine treatment of silver nanowires using an iodine solution and the removal treatment of a silver iodide using a thiosulfate solution are performed by different steps. For example, by the use of a mixed solution containing an iodine solution and a thiosulfate solution, if the treatments described above are simultaneously performed, the silver nanowires in the overcoat layer are dissolved, and as a result, the optical characteristics in the non-electrically conductive region are seriously changed. However, according to the method of the present invention, since the above two steps are separately performed, while the iodized silver nanowires are allowed to remain in the overcoat layer, the silver iodide on the surface of the overcoat layer can be removed, and as a result, the difference in optical characteristics between the electrically conductive region containing the silver nanowires in the overcoat layer and the non-electrically conductive region can be reduced.

Brief Description of Drawings

[Fig. 1] Fig. 1 is an exploded perspective view showing a mobile electronic apparatus mounting a light transmitting electrically conductive member of the present invention.
[Fig. 2] Fig. 2 is a plan view showing a pattern of an electrically conductive layer of the light transmitting electrically conductive member.
[Fig. 3] Fig. 3 is an enlarged view illustrating the pattern of the electrically conductive layer.
[Fig. 4] Fig. 4 is a perspective view showing a basic structure of the light transmitting electrically conductive member.
[Fig. 5] Fig. 5 includes views each showing a method for patterning the light transmitting electrically conductive member.
[Fig. 6] Fig. 6 is a view illustrating one example. Description of Embodiments

An electronic apparatus 1 shown in Fig. 1 is a mobile electronic apparatus and is used as an information communication terminal or a mobile phone or as a mobile game machine, a mobile navigation device, or the like. The electronic apparatus 1 is formed of an input panel 6 and a display panel 5 in combination.
The display panel 5 is a color liquid crystal panel having a backlight or an electroluminescent display element. A rear side film 3 formed of a PET or the like is adhered to the rear side of the input panel 6. An ITO layer 4 is provided over the entire surface of the rear side film 3 and is set to a ground potential. On a front side of the input panel 6, a light transmitting cover panel 2 is fitted.
The input panel 6 is an electrostatic touch panel which is able to detect an input coordinate position by the change in electrostatic capacity. The input panel 6 is formed from a light transmitting electrically conductive member 10 shown in Fig. 4. The light transmitting characteristic of this specification indicates not only a pure transparent characteristic but also indicates, for example, a characteristic having a total light transmittance of 80% or more.
The light transmitting electrically conductive member 10 shown in Fig. 4 has a light transmitting base film 11. The base film 11 is a light transmitting film, such as a PET (poly(ethylene terephthalate)) film, a PC (polycarbonate) film, or a COP (cycloolefin polymer) film. In addition, a light transmitting plate material other than the film may also be used. On a surface 11a of the base film 11, a light transmitting electrically conductive layer 12 is formed. The electrically conductive layer 12 is formed so that a silver nanowire network 13 which is an aggregate of silver nanowires 13a is laminated on the surface 11a, and a light transmitting overcoat layer 14 formed of an acrylic-based material or the like is provided over the network 13.
On the surface 11a of the base film 11, the silver nanowire network 13 is disposed, and an acrylic-based resin in a molten state is supplied thereon to form the overcoat layer 14; hence, as shown by a schematic cross-sectional structure in Fig. 5, the electrically conductive layer 12 has the structure in which in the overcoat layer 14 functioning as a light transmitting resin layer, the silver nanowires 13a are embedded. In addition, as shown by exaggerated cross-sections in Fig. 5, the silver nanowire network 13 is partially projected from and exposed to the surface of the overcoat layer 14 so as to reduce the contact resistance between the electrically conductive layer 12 and a metal layer to be formed thereon.
The thickness of the base film 11 is approximately 50 to 300 µm, and the thickness of the electrically conductive layer 12 is approximately 100 nm.
In the electrically conductive layer 12 of the light transmitting electrically conductive member 10, the silver nanowires 13a are transformed in a specific region into a non-electrically conductive region 25, and a region in which no transformation is performed functions as an electrically conductive region 20.
As shown in Figs. 2 and 3, the electrically conductive region 20 is partitioned into first electrode portions 21, connection conductive portions 22, and second electrode portions 23.
As shown in Fig. 2, the first electrode portions 21 each have a square shape, a rhombic shape, or the like, and are arranged in a Y direction. A first electrode portion 21 and a first electrode portion 21 adjacent thereto in the Y direction are electrically connected to each other by a connection conductive portion 22 provided therebetween. The first electrode portions 21 and the connection conductive portions 22 are continuously formed.
The second electrode portion 23 is formed to have the same shape and the same area as those of the first electrode portion 21. However, the first electrode portion 21 may be formed to have a different shape and a different area from those of the second electrode portion 23 in some cases. The second electrode portions 23 are formed independently of each other so as to sandwich the connection conductive portions 22 therebetween and are linearly arranged in an X direction. A region between the second electrode portion 23 and the first electrode portion 21/the connection conductive portion 22 is electrically separated by the non-electrically conductive region 25 interposed therebetween.
On the surface of the input panel 6, as shown in Figs. 2 and 3, over the connection conductive portion 22, the non-electrically conductive regions 25 located at the two sides thereof, and the second electrode portions 23 further provided at the two sides of the above non-electrically conductive regions 25, an organic insulating layer 31 is formed. The organic insulating layer 31 is formed of an acrylic-based light transmitting organic insulating material, such as a novolac resin. A bridge wire 32 is formed on the surface of the organic insulating layer 31, and by the bridge wires 32, the second electrode portions 23 arranged in the X direction are electrically connected to each other.
The bridge wire 32 is formed of a wire material, such as Cu, Ni, Ag, Au, or ITO. Alternatively, the bridge wire 32 is formed to have a monolayer using various types of alloy materials. In addition, the bridge wire 32 may also be formed using an electrically conductive laminate layer in which electrically conductive materials are laminated to each other. The bridge wire 31 is formed thin and narrow so as not be easily visually detected.
As shown in Fig. 2, a Y lead electrode layer 35 is connected to the first electrode portions 21 connected in the Y direction. As shown in Fig. 1, first land portions 36 are formed at a marginal portion of the input panel 6, and the Y lead electrode layers 35 are separately connected to the corresponding first land portions 36. The second electrode portions 23 connected by the bridge wires 31 in the X direction are connected to X lead electrode layers 37 in the corresponding lines. The X lead electrode layers 37 are separately connected to the corresponding second land portions 38.
In the input panel 6, although an electrostatic capacity is formed between the first electrode portion 21 and the second electrode portion 23, when a finger is brought into contact with the surface of the cover panel 2, an electrostatic capacity is formed between the finger and the first electrode portion 21 or the second electrode portion 23.
When a pulse drive electric power is sequentially applied to the first electrode portions 21 in each line, and current values detected from all the second electrode portions 23 are measured, the first electrode portion 21 which is closest to the finger can be calculated. In addition, when a pulse drive electric power is sequentially applied to the second electrode portions 23 in each line, and current values detected from all the first electrode portions 21 are measured, the second electrode portion 23 which is closest to the finger can be calculated.
In addition, according to the present invention, the input panel is not limited to a panel in which the first electrode portions 21 and the second electrode portions 23 are formed on the same surface of the base film 11 and may be a panel in which two films, that is, a film on which electrodes are sequentially provided in the X direction and a film on which electrodes are sequentially provided in the Y direction, are laminated to each other. Alternatively, a panel in which independent electrode portions are provided and are separately connected to the corresponding land portions 36 may also be used.
Next, a method for patterning the electrically conductive layer 12 of the light transmitting electrically conductive member 10 into the electrically conductive region 20 and the non-electrically conductive region 25 will be described.
In Fig. 5(A), a cross-sectional structure of the light transmitting electrically conductive member 10 before patterning is schematically shown. The electrically conductive layer 12 is provided on the surface 11a of the base film 11. In the electrically conductive layer 12, the silver nanowire network 13 is embedded in the overcoat layer 14. Although exaggeratedly shown in the drawing, the silver nanowires 13a are partially exposed to the surface of the overcoat layer 14.
On the electrically conductive layer 12, a positive type or a negative type photoresist, or a film resist is formed. The photoresist is formed by various types of methods, such as a spin coating method or a roll coating method, to have a thickness of approximately 1 to 5 µm. In the case in which the film resist is used, a resist having a thickness of approximately 20 µm is used. By the use of a mask and an exposure apparatus, the photoresist is partially exposed. In the following developing step, the exposed electrically conductive layer is developed with an alkaline solution such as TMAH, so that partial resist layers 41 remain as shown in Fig. 5(A).
In the electrically conductive layer 12, the resist layers 41 are allowed to remain on portions to be formed into the electrically conductive regions 20 which form the first electrode portions 21, the connection conductive portions 22, and the second electrode portions 23, and a photoresist on a portion to be formed into the non-electrically conductive regions 25 is removed.
Next, a treatment is performed so that the electrically conductive layer 12 which is not covered with the resist layers 41 is changed to be non-electrically conductive.
For this treatment, an iodine solution is used. The iodine solution is an iodine-iodine salt solution, such as an iodine-potassium iodine solution. The iodine-potassium iodine solution is a solution in which iodine is dissolved in a potassium iodine solution, and a solution containing 0.05 to 1.0 percent by mass of iodine and approximately 0.1 to 5.0 percent by mass of potassium iodine is used.
When the light transmitting electrically conductive member 10 on which the resist layers 41 are formed is dipped in the iodine-potassium iodine solution for approximately 0.5 to 10 minutes, the solution permeates the inside of the overcoat layer 14 in a region which is not covered with the resist layers 41, and the silver nanowires 13a are at least partially iodized and transformed into a silver iodide.
In the region which is not covered with the resist layers 41, since the silver nanowires 13a are iodized, the surface resistivity of the electrically conductive layer 12 in the region described above is increased, and a non-electrically conductive region 25 which exhibits substantially an electrically insulating function is formed.
However, when the non-electrically conductive treatment is performed using an iodine-potassium iodine solution, in the region which is formed into the non-electrically conductive region 25, the silver nanowires exposed to the surface of the overcoat layer 14 is iodized, and as a result, a white cloudy or a whitened metal compound is generated.
Accordingly, in the following step, by the use of a thiosulfate solution, the white cloudy or whitened metal compound, such as a silver iodide, on the surface of the overcoat layer 14 is removed. As the thiosulfate solution, a sodium thiosulfate solution at a concentration of 1.0 to 25 percent by mass is used. When the light transmitting electrically conductive member covered with the resist layers 41 is dipped in the solution for approximately 10 to 60 seconds, the metal compound, such as a silver iodide, exposed to the surface of the overcoat layer 14 can be removed.
When the resist layers 41 are removed using a resist stripper, as shown in Fig. 5(C), the electrically conductive layer 12 is partitioned into the electrically conductive regions 20 and the non-electrically conductive regions 25. As shown in Figs. 2 and 3, by the electrically conductive regions 20, the first electrode portions 21, the connection conductive portions 22, and third electrode portions 23 are formed.
Since containing a silver iodide, the non-electrically conductive region 25 has a non-electrical conductivity, or the surface resistivity thereof is significantly higher than that of the electrically conductive region 20. In the non-electrically conductive region 25, since iodized silver nanowires are allowed to remain in the overcoat layer 14, the difference in optical characteristics from those of the electrically conductive region 20 in which the silver nanowires are present is reduced. Hence, between the electrically conductive region 20 and the non-electrically conductive region 25, a significant difference in transmission characteristics of display light emitted from the display panel 5 may not be generated.
In the non-electrically conductive region 25, a silver iodide generated on the surface of the overcoat layer 14 is removed. Alternatively, the amount of a silver iodide generated on the surface of the overcoat layer 14 is significantly reduced as compared to the amount of the silver nanowires 13a exposed to the surface of the overcoat layer 14 in the electrically conductive region 20.
In the patterning method described above, the iodizing treatment of the silver nanowires 13a using an iodine solution and the removal treatment of the white cloudy metal compound, such as a silver iodide, using a thiosulfate solution are performed in different steps. For example, when the above treatments are simultaneously performed using a mixed solution containing an iodine solution and a thiosulfate solution, the silver nanowires in the overcoat layer are dissolved, and as a result, the optical characteristics of the non-electrically conductive region are seriously changed. However, in the method described above, since the two treatment steps are separately performed, while iodized silver nanowires are allowed to remain in the overcoat layer, the metal compound, such as a silver iodide, on the surface of the overcoat layer can be removed, and hence, the difference in optical characteristics between the electrically conductive region in which the silver nanowires are present and the non-electrically conductive region can be reduced.

EXAMPLES

(Example)

By the use of a light transmitting electrically conductive member 10 in which an electrically conductive layer 12 formed of a silver nanowire network 13 and an acrylic-based overcoat layer 14 and having a thickness of approximately 100 nm was formed on a surface of a PET film, as shown in Fig. 6, an electrically conductive region and a non-electrically conductive region were patterned.
In an iodizing treatment of the silver nanowires, dipping was performed for 120 seconds in an iodine-potassium iodine solution containing 0.1 percent by mass of iodine and 0.5 percent by mass of potassium iodine. In a removal treatment of a metal compound, such as a silver iodide, remaining on the surface of the overcoat layer 14, dipping was performed for 30 seconds in a sodium thiosulfate solution at a concentration of 10 percent by mass.

(Comparative Example)

By the use of the same light transmitting electrically conductive member 10 as that of Example, a region having the same area as that of the non-electrically conductive region shown in Fig. 6 was etched using an aqua regia-based etchant to dissolve the silver nanowires in the overcoat layer 14, and the electrically conductive member thus processed was used as Comparative Example.
In the following Table 1, the optical characteristics of Example are compared to those of Comparative Example.
In Example of Table 1, the haze and the total light transmittance of the electrically conductive layer before the treatment, that is, the electrically conductive region, are compared to the haze and the total light transmittance of the non-electrically conductive region obtained by the treatment using an iodine-potassium iodine solution and the treatment using a thiosulfate solution.
In Comparative Example of Table 1, the haze and the total light transmittance of the electrically conductive layer before the treatment, that is, before the etching, are compared to the haze and the total light transmittance of the region obtained by etching the silver nanowires using an aqua regia etchant.
In Example, it is found that between the electrically conductive region and the non-electrically conductive region, a significant difference in total light transmittance is not generated. It is found that in Example, although the haze in the non-electrically conductive region is decreased as compared to that in the electrically conductive region, the haze in the non-electrically conductive region is significantly superior to that of the region obtained by removing the silver nanowires in Comparative Example.

In addition, in Example, the optical contrast between the electrically conductive region and the non-electrically conductive region is as shown in Fig. 6.

[Table 1]

	AgNW ETCHANT	FILM CONDITIONS	OPTICAL CHARACTERISTICS
	AgNW ETCHANT	FILM CONDITIONS	HAZE	LIGHT TRANSMITTANCE (%)
COMPARATIVE EXAMPLE	AQUA REGIA BASE	BEFORE ETCHING	0.95	89.92
COMPARATIVE EXAMPLE	AQUA REGIA BASE	AFTER ETCHING	0.25	92.08
EXAMPLE	IODINE BASE	BEFORE TREATMEMT	0.92	89.79
EXAMPLE	IODINE BASE	AFTER TREATMENT	0.75	90.15

Reference Signs List

1: electronic apparatus
5: display panel
6: input panel
10: light transmitting electrically conductive member
11: base film
11a: surface
12: electrically conductive layer
13: silver nanowire network
13a: silver nanowires
14: overcoat layer
20: electrically conductive region
21: first electrode portion
22: connection conductive portion
23: second electrode portion
25: non-electrically conductive region
41: resist layer

Claims

A light transmitting electrically conductive member in which an electrically conductive layer including an overcoat layer and silver nanowires embedded therein is formed on a surface of a light transmitting base material,
wherein the electrically conductive layer is partitioned into an electrically conductive region and a non-electrically conductive region having a high surface resistivity as compared to that of the electrically conductive region, and in the non-electrically conductive region, the silver nanowires embedded in the overcoat layer are at least partially iodized, and
a silver iodide is not exposed to a surface of the overcoat layer in the non-electrically conductive region, or the amount of a silver iodide exposed to the surface of the overcoat layer in the non-electrically conductive region is small as compared to the amount of silver nanowires exposed to a surface of the overcoat layer in the electrically conductive region.
A method for patterning a light transmitting electrically conductive member, the method using a light transmitting laminate material in which an electrically conductive layer including an overcoat layer and silver nanowires embedded therein is formed on a surface of a light transmitting base material, and the method comprising the steps of:
covering a part of the electrically conductive layer with a resist layer;

treating a surface of the electrically conductive layer which is not covered with the resist layer using an iodine solution to at least partially iodize the silver nanowires; and

applying a thiosulfate solution to the surface of the electrically conductive layer which is not covered with the resist layer to remove a silver iodide exposed to a surface of the overcoat layer.
The method for patterning a light transmitting electrically conductive member according to Claim 2, wherein the iodine solution is an iodine-potassium iodine solution.
The method for patterning a light transmitting electrically conductive member according to Claim 3, wherein in the iodine-potassium iodine solution, the concentration of iodine is 0.05 to 1.0 percent by mass, and the concentration of potassium iodine is 0.1 to 5.0 percent by mass.
The method for patterning a light transmitting electrically conductive member according to any one of Claims 1 to 4, wherein the thiosulfate solution is a sodium thiosulfate solution.
The method for patterning a light transmitting electrically conductive member according to Claim 5, wherein the concentration of sodium thiosulfate is 1.0 to 25 percent by mass.